Unit 2 Flashcards
___________ and _____________ processes work together to create soil aggregates.
Cohesion and fragmentation
It is an unconsolidated, or loose, combination of organic and inorganic materials.
Soil
Granular soil have good load bearing qualities. It is permeable hence they drain easily. They are comparatively incompressible when subjected to static loads. Not subject to changes in strength or volume due to variation in after content.
Determine the particle size distribution of soil and it is used to classify/identify the soil.
Particle Size Analysis of Soil
The lowest moisture content at which the soil will flow upon the application of a very small shearing force.
Liquid Limit
The minimum moisture content at which the soil can be readily molded without breaking or crumbling.
Plastic Limit
It is a process of increasing soil density and removing air, usually by mechanical means.
Compaction
This involves the granular rearrangement of soil particles at a number of moisture contents ranging from slightly sry to very wet by a specified amount of energy applied on a specified manner.
Compaction Test
The purpose of compaction test is to determine the amount of mixing water (Optimum Moisture Content) and Maximum Dry Density (True or False)
True
It is a method of evaluating the relative quality of subgrade, subbase, and base soil for pavements.
California Bearing Ration
This test evaluates the structural strength of coarse aggregate. It gives an indication of quality as determined by resistance to impact and wear.
Abrasion Test
These are the most mined material in the world. Defined as inert, granular & inorganic materials that normally consist of stone or stone - like solids.
Aggregates
Approximately _____ of the volume of Portland cement concrete is occupied by aggregates. They provide compressive strength and bulk to concrete.
3/4
Extracted from larger rock formations through an open excavation (quarry) and reduced to usable sizes by mechanical crushing or grinding (sand, crushed limestone, gravel)
Natural Aggregates
To evaluate/determine the particle size distribution of aggregates.
Sieve Analysis / Grading Test
_____________ or _____________ of aggregates is an important characteristic because it determines the paste requirement for workable concrete.
Grading or size distribution
A sample of well-graded aggregate containing minimum voids will require _____________ to fill up the voids in the aggregates.
minimum paste
Maximum size of aggregate (MSA) should not be greater than thickness of section or slab divided by 4 (True or False)
True
The smallest sieve through which 100 percent of the aggregate sample particle pass. “One sieve large than the nominal maximum size.”
Maximum Size Aggregates
The largest sieve that retains some of the aggregate particles but generally not more than 10 percent by weight. It is one size larger than the first sieve to retain more than 10 percent of the material.
Nominal Maximum Size of Aggregates
The ration of the mass of a solid or liquid to the mass of an equal volume of distilled water 4°C.
Specific Gravity Aggregates
Full absorbent
Oven dry
Dry at the particle surface but containing some interior moisture, thus still somewhat absorbent Saturated surface dry (SSD) - neither absorbing water from nor contributing water to the concrete mixture.
Air Dry
Containing an excess of moisture on the surface (free water).
Damp or wet
The test determines the presence of injurious organic compounds in natural sand (to be used in cement mortar or concrete).
Organic Impurities in Fine Aggregates
This is usually being used for Bituminous or Asphalt Mix
Composite Aggregates
